Omnibox UI Experiments: Add vertical margin variations to about:flags

components/omnibox/browser/omnibox_field_trial.cc

Index: components/omnibox/browser/omnibox_field_trial.cc
diff --git a/components/omnibox/browser/omnibox_field_trial.cc b/components/omnibox/browser/omnibox_field_trial.cc
index 2d7430638ea682ae1d1ce618f2c2bdeb10a9e877..fe37056d252e74ee5315aacd73316aa2a61a6ad7 100644
--- a/components/omnibox/browser/omnibox_field_trial.cc
+++ b/components/omnibox/browser/omnibox_field_trial.cc
@@ -80,6 +80,10 @@ const base::Feature kZeroSuggestSwapTitleAndUrl{
 const base::Feature kDisplayTitleForCurrentUrl{
     "OmniboxDisplayTitleForCurrentUrl", base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Feature used for UI experiments.
+const base::Feature kUIExperiments{"OmniboxUIExperiments",
+                                   base::FEATURE_DISABLED_BY_DEFAULT};
+
 }  // namespace omnibox
 
 namespace {
@@ -736,6 +740,9 @@ const char
     OmniboxFieldTrial::kZeroSuggestRedirectToChromeAdditionalFieldsParam[] =
         "ZeroSuggestRedirectToChromeAdditionalFields";
 
+const char OmniboxFieldTrial::kUIExperimentsVerticalMarginParam[] =
+    "UIExperimentsVerticalMargin";
+
 // static
 int OmniboxFieldTrial::kDefaultMinimumTimeBetweenSuggestQueriesMs = 100;